Understanding Whole Building Life Cycle Assessments

By Dallas Terry – Director of Decarbonization

Sustainable Investment Group (SIG)

As sustainability becomes a growing priority in architecture, urban planning, and construction, Whole Building Life Cycle Assessments (WBLCAs) are playing a key role in helping designers, engineers, and builders minimize the environmental impact of their projects. By evaluating the embodied carbon and other environmental impacts of building design and material selection, WBLCAs provide insights into embodied carbon footprints at every stage of the building process. The following provides an overview of how WBLCAs can be effectively used throughout the different design phases of a new construction project.

1. Pre-Design and Conceptual Design: Informing High-Level Decisions

In the earliest phases of a project, WBLCAs offer a rough estimation of a building’s potential embodied carbon footprint. These phases also present some of the most significant opportunities to make a lasting impact on embodied carbon:

Building size, shape, and programming: Fundamental decisions around the building’s size, shape and use can significantly influence the quantity of materials required, including high-carbon materials like concrete and steel. Adjustments made early on can significantly reduce embodied carbon with less budgetary implications.
Benchmarking and setting embodied carbon targets: By understanding potential environmental impacts through embodied carbon benchmarking and relevant analysis, teams can set clear, data-driven carbon reduction goals early on in the project, such as percent reduction targets or carbon intensity limits.

2. Schematic Design: Material and Structural Decisions

As the design becomes more detailed, WBLCAs can still guide significant opportunities for embodied carbon reduction. During the schematic design stage, architects and engineers can compare different material and system options to make synergistic material selections:

Evaluating structural systems: WBLCAs help assess various structural systems (e.g., steel, concrete, hybrid) based on their embodied carbon impacts. Teams can choose materials that balance sustainability, cost, strength, and durability.

Envelope and building components: WBLCAs allow the comparison of different building envelope material packages, such as various wall and roof assemblies. Selecting low-carbon material packages at this stage, in collaboration with energy modeling, helps optimize designs for both embodied and operational carbon.

3. Design Development: Refined Analysis and Optimization

By the design development phase, WBLCAs can be used for more detailed analysis, focusing on optimizing the final selection of materials, products, and systems:

Optimizing material selections: With more accurate data on quantities and specifications, WBLCAs help teams choose materials with lower global warming potential (GWP). This can generally be considered a “lower hanging fruit” strategy in using LCAs to reduce embodied carbon.

Improving data accuracy: Finishes and materials that were not previously considered are now often selected, allowing WBLCAs to give a more precise picture of the building’s embodied carbon profile.

Evaluating building systems: Mechanical, electrical, and plumbing (MEP) systems are often selected at this stage and can also be evaluated based on their long-term carbon impact, ensuring that both embodied and operational carbon are minimized.

4. Construction Documentation: Final Adjustments and Certifications

As the design nears completion, WBLCAs play a critical role in finalizing environmental assessments and ensuring compliance with sustainability certifications.

Refined environmental impact calculations: Material selections and quantities are now almost finalized, enabling more accurate carbon calculations. Incorporating Environmental Product Declaration (EPD) data for key products can help improve the precision of key data assumptions in the WBLCA.

Certification and/or Regulation compliance: WBLCAs can be used to achieve points and meet sustainability frameworks such as LEED or BREEAM as well as to meet compliance with regulations such as CalGreen in California or AEGB in Austin.

5. Construction and As-Builts: Tracking Real-Life Performance

Even after the design phase, WBLCAs can continue to provide value during construction and post-construction phases with additional opportunities to improve data accuracy:

Material procurement verification: WBLCAs can be updated further based on available submittal documents and feedback from construction teams.

As-built documentation: A final WBLCA based on as-built drawings can provide the most accurate assessment of the building’s real-world embodied carbon footprint, helping capture any variances between the design and what was ultimately constructed.

WBLCAs are an Integral Part of Sustainable Design

WBLCAs are not a one-time exercise but an evolving tool that is ideally used throughout the entire project lifecycle. From early concept to construction, they provide actionable insights that drive better, more sustainable design decisions. By integrating LCAs at each stage of the design process, architects, engineers, and builders can minimize the environmental impacts of their projects and contribute to a more sustainable built environment. Incorporating LCAs early and revisiting them throughout the project ensures that carbon is considered from the ground up, leading to buildings that are not only functional and aesthetically pleasing but also environmentally responsible.

Ready to integrate WBLCAs into your next project? Our team at Sustainable Investment Group (SIG) specializes in sustainability consulting and life cycle assessments to help you make informed, low-carbon design choices. Contact us today to explore how we can support your goals.

Dallas Terry is the Director of Decarbonization at Sustainable Investment Group (SIG), where he leads the Decarbonization Department, focusing on innovative strategies like energy modeling, embodied carbon assessments, and decarbonization studies. With a strong background in sustainability consulting, Dallas helps clients navigate the path to reducing carbon emissions and meeting regulatory requirements. Passionate about aligning technical solutions with ESG goals, he brings a comprehensive approach to optimizing sustainable building projects.